Ecological Studies On The Bottom Fauna Of Lake Manala, Egypt

Abstract

An ecological survey has been conducted for the benthic Community in Lake Manzala during May and June, 1985. The diversity and distribution of organisms are largely determined by salinity. Mean abundance of benthic fauna ranged from 1494 to 2820 organisms/m2 for sampling transects. Pisidium and Melanoides mollusca dominate the low salinity southern regions, while Cerastoctenna, Abra and Alvania species dominate the saline sectors.

Two other species of considerable importance in the lake are the gastropods Buiinus tnincatus and Biomphalaria alexaadrina as both function as schistosomiasis vectors. It appears that areas of the highest incidence of the disease in humans correspond with lake areas characterized by the presence of these snails. The snails are most abundant in the low salinities and high waste loading in the southern sector of the lake.